Ladder operating mechanism



Oct. 6, 1953 E. G. HUMPAI. ET AL v 21,654,524

LADDER OPERATING MECHNISM 4 Sheets-Sheet l Filed July 7, 1949 /Par 0. PALM# Oct. 6, 1953v E. G. HUMPAL ETAL LADDER OPERATING MECHANISM Filed July 7, 1949 4 Sheets-Sheet 2 III...

VENToRs Oct. 6, 1953 E G HUMPAL ErAL 2,654,524

ALADDER OPERATING 'MECHANISM Filed July 7, 1949 4 Sheets-Sheet i5 INIVENTORJ'O fnac/v6 6. fil/PAL 1f For .0. 5M a4# Oct 6, 1953 E. G. HUMPAL ETAL 2,654,524

LADDER OPERATING MECHANISM Filed July Y'7, 1949 4 Sheets-Sheet 4 Aff/amaai Patented Oct. 6, 1953 UNITED STATES ?ATENT FFICE 2,654,524 LADDER OPERATING MECHANISM Eugene G. Humpal and Roy O. Balogh, Cleveland, Ohio,` assgnors, by mesne assignments, to McCabe-Powers Auto Body Co., St. Louis, Mo.,

a. corporation of Missouri Application July 7, 1949, Serial No. 103,484

4 Claims. (Cl. 228-8) This invention relates to a mechanism for mounting a ladder and controlling it to enable it to be swung laterally and elevated and extended as desired. An object of the invention isto provide eiTective controlling mechanism for such movements so arranged that they may all be operated by one operator from a single position. Our extension ladder is pivoted to a supporting member which is swiveled on an upright standard. This standard, if desired, may be carried by a transporting vehicle. Suitable manually operated mechanism between the standard and the supporting member is provided to swingthe ladder laterally. Hydraulic mechanism between the 'supporting member and ladder enables the ladder to be swung upwardly on its pivot or lowered into horizontal position for transportation.

Mechanism on the ladder itself including its extension provides means for eifecting such extenvsion under manual control.

The upright standard is preferably hollow and provides the receptacle for the liquid used in the hydraulic operation. The'control valves for the hydraulic operation are mounted on the swiveled supporting member. We provide two hand wheels von opposite sides of the device one for operating 'the lateral swinging mechanism and the other for eifecting the ladder extension. We provide preferably a foot lever for operating the control valve. The ladder carries a depending support for the operator between the two hand Wheels 'and adjacent the foot lever, so that in one position he may operate all three controls.

Our invention includes the features of operation above-mentioned, and also the more specific embodiment thereof illustrated in the accompanying drawings, which show a preferred form of our invention.

In the drawings, Fig. 1 is a side elevation of our ladder and its support mounted on a transporting vehicle, of which a portion is shown; Fig. 2 is a horizontal section in a plane indicated by the line 2-2 on Fig. l, showing the manually operated gearing for swinging the ladder laterally; Fig. 3 is a diagram illustrating the conduits and connections and valves for controlling the hydraulic operation which swings the ladder upwardly and downwardly on its pivot; Fig. 4 is a sectional side elevation, in a plane parallel with Fig. 1 but on a larger scale, showing the hydraulic operation and the lateral swinging mechanism; Fig. 5 is a vertical section through the ladder supporting member in a plane at right angles to Fig. 4, as indicated by the line 5--5 thereon, but on a smaller scale; Fig. 6 is a view 'in the nature of a plan, as indicated by the line 2 6-6 on Fig. 1, showing the mechanism for extending the ladder; Figs. '7J 8 and 9 are diagrams showing the position of the controlling valves respectively for holding the ladder at any angle and for raising it and for lowering it.

In Fig. 1 we have indicated at A any suitable transportation vehicle which carries an upright hollow standard I0 on which our ladder is mounted. This vehicle also carries a suitable power-operated pump, not shown.A The standard IIl which is hollow forms the reservoir for liquid used for the hydraulic operation, and a conduit from the pump communicates with this hollow standard. A conduit within the standard as hereafter explained, leads to the control valve for operating the hydraulic .ladder lifting mechanism, and a return conduit from the control valve leads to the interior of this reservoir.

Referring more particularly to the hollow vertical standard IU, this is best shown in Fig'. 4,

and comprises an uprightcylindrical body reinltube I0 and welded to it. These two discs I3 and I4 are additionally locked together by a bolt I5. Thus all of the parts mentioned are rigidly connected together for effectively carrying the standard I 0 in vertical position.

In addition to being a receptacle, the tubular standard I0 forms the support for the rotary member to which the ladder is pivoted. This is eiected by a head I8 on the tube I0 which carries an upright cylindrical extension I9 on which other members are mounted as hereinafter eX- plained.

The swiveled ladder support is a tubular member 2l) surrounding the member I 0 and at its lower end carries a rubbing bearing 2I engaging the exterior of the reinforcing sleeve II. At the 'upper end of the cylinder 29 is a transverse plate 22 to which is bolted a collar 23. A'rolling bearing is provided between the collar 23 and the stationary tubular support I9. As indicated, in Fig. 4 this bearing comprises a double conical roller arrangement 24 which provides both for the thrust and rotation.

'rho horizontal plate 22 at the 'oop ofthe cylinder 20 is of rectangular formation, the smaller dimension of which is the same as the external diameter of the tube I IJ. Embracing this rectangular plate is a box-like rectangular structure having side plates 25, tangent to the cylinder 20 and welded to it, end plates 26, partitions 21 and a top plate 28. This rectangular extension of the tube 20 furnishes the pivotal support for the ladder, as hereinafter explained.

The mainladder. hasa pair of side rails30. and suitable. 31;. These side rails are pivoted to the rotary supporting structure by means of a pair of pivot bolts 32 which occupy stationary' sleeves 29 mounted in the vertical plates 26 and 21 carried by the tube 20 and" welded' tothe plates, as illustrated in Fig'.` 5.. IIlhe. ladder rails are journaled on the bolts; 32 whichhaye: heads. 33 and nuts 34 screwing ont'o their inner/ends;

form a lock, holding the bolts in stationary position and thus effectively pivoting, the ladder to, the rotating member 20.

The stationary extension I9 of the head. |185 o' the standard rigidly carries a worm wheel 40 located above.. the bearing 24 and keyed. tol the extension... The partitionwalls 2T of the box-like extension. of. the tube 2|)` carry bearings 42. (Fig. 2) in. which isV rotatively. mounted. a. shaft 43 carryingv a WormY 44. meshing with the. worm w-heelY 40.. In ther outer end. of. the shaft 43 is a-.hand wheel 45.A handwheel. and. the worm gearing. provide readily. operable manual means for turning. the member 20fand the-parts. it. carr-ies. on the standard I0 and thus swinging. the ladder 1aterally,.as desired..

' Slidablyguided; on the ladder rails- 30. are the rails-50. of the extension. ladder.. thisladder carryingY suitable cross. rungs Any. of. the

'usual1 means for eiecting the. sliding` connection between the twoladders.. may be. employed.; hence,.they are omitted. in Fig.. 6;Y which is-con.- cerned with' the. operatingv mechanism.

Mounted oni therails 30. ofthernairr ladder is a. rctaryshaftZ carrying. a-drum 53 about. which iss Wound: a. cable 54. rIlhis cable extends up,- wardlyvl overA pulleys and.. operates to raise the extension.. ladder. Asti shown, the cable 54= passes over. a pulley 55- carried by the outermost rung 3|. Yof the. main ladder and thence downwardly beneath-1. and acrosstwo pulleys.` 5B carried by the extensionladder. and thence-upwardly where itisanchored at 51. toe-the outermos-t rung of the mainV ladder. A suitable: hand wheel 58: on.- the shaft; 5.2. provides for rotating it; and: thus paye ingfthe cable-in4 or out terr-aise the. extension ladder with referenceto-the'main. ladder or tocorrtrol: itsdescent.

At their rear ends the-.rails 30=of the main lad,- der. carry a cross rod B|- on which is pivotally connected a. depending: foot: support 60 whichhas preferably several` cross bars 62. to supportv the cperatorinainy elevation desired. It willi beseen that. the operator. standing on one: of the cross hars 62 and facing.r thestandard and laddersv is in position to operate the hand Wheel 45` by his right hand to swing. the ladders'laterally, and by hisA lef-t. hand tofoperate. the handl wheel'. 58 to operate: the extension. of'. the ladder.

The hydraulic operating member comprises'y a cylinder.' 1.0., and` a piston. 1. li within it. on the= lower endi of a.: rod 12. rllhe' cylinder at its lower end i'spiyotally connected'i to the rotating supportY 230, and the pi'stonrod at its upper endis pivotally connected tol struts depending from the ladder.

As'showrr in- Figs. l and 4, we secure a collar 13 about the lower portion of the tube 20. This collar has a radially' projecting ear 14 Whichis embraced by a bifurcated. ear 'l5 projecting down- Ward from theheadl of the. cylinder. A.A pinV 1.1

IIE

pivots these members together. The upper end of the piston rod is shown as pivoted to a tting 36 Which is at the junction of a pair of struts 37 and 38 depending from the ladder 30. These struts extend between the rails of the ladder and are rigidly secured to the cross members secured to the ladden. one of these crosss members being shownatfv in Fig. 4.

Pivoted to one side of the rotary supporting member 20 is a foot lever 8|, which operates the valve alsoA mounted on the member 20, which controlsV thev passage of fluid under pressure thro11gi3..the. conduit. designated 5 at the lower portion-.oi` the cylinder. This foot lever 8| is in position to'be Operated by the right foot of the operator'standingf on the support 60. The operator may thus.actuate the Valve to transmit fluid under pressure to the bottom of the cylinder toishove the piston upwardly and thereby swing the ladder on its pivot 32; or to hold the liquid within the cylinder and. thereby. hold. the ladder in'. a. definite. position, or. to release such liquid and. thereby,- allow.. the. ladder to. descend. by its own weight.. This hydraulic operation. will be best understood vfrom thel arrangement. of conduits. in Figs. l. and 4. and. the diagrams of 3 and:7'8.and..9..

'Ehe conduit.A designated 6. in. Fig.Y 4. and in. the diagrams-leads to. the pump. from the-lower portiorrei the receptacle |50, being. coupled-.toa nip.- ple |.Er discharging. into the. receptacle.. Another conduit designated. comesffromthe pump. to, a coupling 82. which` connectsv it with.v an inside elbow 83l from. which. elbow a conduit. 8.4 leads upwardly throught thef hollow bearing and.. stationary sleeve I9 toastationary` cylindrical; plug 85.carried.by such. sleeve.I This-plug 85 has' in its exterior surface: anannular groove. 86 with. which thef conduit 8A. communicates.. Surrounding the stationary plug 85 is a..sleev.e: 81. carried. byA the top portionof.'` the rotating member. 20.4 Extending outwardly; from. this sleeve 81. is a conduit 88 passing tofthe exterior of. the rotary. support and thence continuing downwardly by an external conduit. 89, leading; to. the. control. valve.. 80..

It. results' from the connection: just,v described that. the control. Valve. is` always., in communica.-

tion-.with=. the conduit from. the pumpfirrespeci- Ytive-of the lateral positionof. theladder. and the corresponding lateraL position: of; the control valve carried .bythe rotating, member 20.

The. stationaryA cylindrical plug 85Y is,I provided with another internal verticalI passageway in communication. witha another annular groove. 90 itsy exterior.: A.. conduit. 92, leadsl downwardly f-romthis passageway to the interior of thecylinder.' |z0z. The; same verticaal passageway extends to the top of the plug where it communicates 'withrtha interior of' ar breather valve having a removable capI 9S. A conduit; 95 extendsv from the sleevef 81T- outwa'rdly throughV the exterior of Vthe platex 25 ofY the`V rotary member and.V is1 there connected. to a. conduit designated. 2 leading to thefcontrolavalve.

It wiil be-seerr that the conduit 2from thecontrol valve i'sy always in. communication with the 'interior' of' the receptacle HI` irrespective of the lateral' position of the ladder and control valve. The removal of: the capL 93" ofV the breather furnishes ready means for supplying fluid as may be necessary tothe interior of the receptacle |.0 through the passageway 92;

Associated'. with the hydraulic control 80 isa pilot-operated. check valve |00. also mounted. on the cylinder 20. This pilotfoperated checkvalve.

as shown in Figs. 7, 8 and 9, includes a closed casing having an internal valve seat IUI; a plug |02 cooperating with said seat; a spring |03 tending to press the plug to its seat, and a piston |05 in the cylindrical portion of the casing having a piston rod adapted to pass through the valve seat and unseat the valve plug |02.

The conduit from the cylinder is connected to the pilot-operated valve on the plug side of the valve seat. A conduit 3 from the control valve leads to the cylinder on the other side of the seat and in advance of the piston |05, and a conduit 4 leads from the control valve to the pilot-operated check valve on the other side of the piston |65.

In the normal, idle or holding position of the ladder lifting mechanism, the plug |02 of the pilot-operated check valve is held on its seat by the spring 03. The con trol valve 80 is indicated as having a multi-piston cylindrical controlling plug H5. In the holding position, Fig. 7, this controlling plug blocks both the passageways 3 and 4. Thus the conduit from the pump is connected merely through the diagonal passageways of the piston of the plug to either of the conduits 2 (two parallel conduits 2 being shown in Figs. 7 and 8) back to the reservoir I0.

As the reservoir is in constant communication with the pump via the conduit 6, the result is that in the neutral position the pump may operate idly, merely circulating liquid to and from the reservoir.

When it is desired to raise the ladder the control plug ||0 is shifted by its foot lever 8| into the position shown in Fig. 8. In this position the conduit from the pump is coupled to the conduit 3 so that :duid under pressure passes to the pilot-operated check valve and by its pressure forces the plug |02 from its seat and thence passes to the conduit 5 and the cylinder to raise the ladder. It will be noticed that in this position of the control valve the additional conduit 4 to the check valve is idle, being merely coupled to the reservoir.

To lower the load, the valve plug ||0 is shifted in the opposite direction into the position shown in Fig. 9. In this position the conduit 3 between the control valve and the check valve is disconnected at the control valve from the pump but is connected with the reservoir. On the other hand, the line from the pump is coupled to the line 4, conveying pressure to the cylinder portion of the check valve to force the plunger into position to unseat the valve. This couples the conduit 5 from the cylinder with the conduit 3 and thence to the conduit 2 back to the reservoir, so that the pressure liquid in the cylinder is freed and the ladder may descend by its own weight. When it has descended the desired distance, a shifting of the plug ||l to neutral position (Fig. 7) terminates the descent of the ladder.

By the simple provision of the control valve, the pilot-operated check valve and conduits, as described, the operator standing on the support 60 may readily eiect the raising or holding or lowering of the ladder, as described.

It will be seen from the description given, and the illustrations in the drawings, that we have provided a self-contained supporting, operating and controlling device adapted to be mounted on a vehicle or other suitable support and serving not only to carry the ladder during transport of the vehicle but to operate it to swing it, raise it, and extend it, as desired, all such operations being readily controlled by one man standing on the supporting device depending from the ladder.

By making the tubular stand for swivelly supporting the pivoted ladder hollow and providing it with suitable conduits, we save the necessity of any outside tank. We have also housed the lateral turning mechanism within a hollow portion of the ladder-supporting device, where it is thoroughly protected. This same rotary supporting member also carries the control valve, its associated pilot-operated check valve, and the controlling foot-lever. We have thus consolidated the various requirements and their operation into a comparatively small space all selfcontained and ready for mounting, as desired, on any suitable vehicle or elsewhere.

We claim:

1. The combination of an upright standard, a supporting member swiveled on the standard on a vertical axis, a ladder pivoted to the supporting member on a horizontal axis, an operators support disposed in downwardly extending relation to, and rotatable with, the ladder, a stationary worm wheel carried by the standard in a horizontal plane, a rotatable worm mounted in the supporting member and coacting with the worm wheel, and means adapted for manipulation by an operator on said operators support for turning the worm.

2. The combination of an upright stationary cylinder adapted to form a supporting standard and a reservoir, a head on said cylinder, said head carrying a tubular plug having two longitudinal passageways therein, conduits connecting one of said passageways with a source of fluid supply under pressure and connecting the other passageway with the interior of the cylinder, said passageways terminating in independent annular grooves on the exterior of the plug, a tubular supporting member surrounding said cylinder and mounted to turn on the axis of the cylinder, said supporting member having a sleeve surrounding said plug, a pair of conduits leading from said sleeve to the exterior of the supporting member and there connected with a control valve carried by the supporting member, a ladder pivoted to the supporting member, a piston and cylinder connected to the supporting member and ladder for raising the ladder, :and a conduit between the control valve and the cylinder for transmitting iiuid under pressure to the cylinder to raise the ladder.

3. The combination of a stationary upright hollow cylinder forming a supporting standard and a reservoir, a head on said cylinder, a tubular supporting member surrounding the cylinder and operatively bearing against the exterior of the cylinder near the lower end of the supporting member, an axial thrust bearing operatively mounted between the cylinder and the head on said standard, a stationary worm wheel carried by the head of the cylinder, a worm journaled in the supporting member to coact with said worm wheel, a stationary tubular plug carried by said head above the worm wheel, a sleeve carried by the supporting member surrounding said plug, two independent conduits carried by the supporting member and extending through said sleeve to communicate respectively with the passageways in the plug, one of said passageways communicating with the interior of the standard, a conduit within the standard connecting the other passageway with an external source of supply, a ladder pivoted to said supporting member, a. piston and cylinder couple one end of which is piyothto-tlielddor and` theV other end-,of which iss piyoted; to, the` sumoorting` member near the lowerycndlthereofaacontrol valve carried by. the sun-potting memberand` communicating with saidr two .conduits leading. to tlie` plug, and a conduit.; @,'Stablishing` communication from the controlValve to thecylinder of saidcouple.

4; Alli-aerial ladder comprising a base, a hollow vertical-,cylinder mounted on and extending upwardlyfrorn the base vand 'closed at its ends to providea reservoir for hydraulic uid, pump-means fon-Supplying hydraulic fluid under pressure to tnereservoi-n atubular: post mounted concentrically upon-the cylinder Afor rotation about the Verticak agristhereof, a ladder element mounted on the upper end `of thepost forhrockable movement about a horizontal axis, an extensible hydraulic piston-cylinder assembly rockably connected at its one end` to the post and at its other end to theladderl element outwardly o the horizontal axisabout which said latter element pivots, a iirst'conduitconnecting the reservoir with the piston-cylinder assembly, a check-valve internosed in said line, said check-valve having hyd raulic. actuating means. whereby it may be opened, a second conduit connecting the hydraulic, actuating means of the check-valve to the reservoir, a multiplex valve interposed in both conduits and connected also by an auxiliary EUGENE G. HUMPAL. ROY O. BALOGH.

References Cited in the; le of this` patent UNITED STATES PATENTSl 

